Hum issue - driving me more crazy

Yeah, if going balanced fixes it, go for it. It could take a long time to figure out what is happening. Enjoying music is much more fun. ;-)

Always use balanced mode when possible. More equipment should be balanced.

PS Audio has something called a Humbuster (now version 3).
Never tried it.

Humbuster is specifically for removing DC from your AC line. So it will solve problems of transformer hum coming from the chassis of an amp, etc. But doesn't address the sources of hum that come out of speakers.

Great device if DC on the line is your problem, as it was for me at my old apartment.

All the posts that I have read try to assume a particular problem. However, this is similar to auto repair shops not doing a detailed diagnostic and simply replacing components until the problem is fixed. First, under no circumstance do you lift any ground by using cheaters. People do this often to eliminate potential ground loops, but a) This simply mask the problem but does not fix it, b) you have now created a situation whereby you, your family, pet, etc. may become a better ground when there is a fault and someone could get seriously hurt.

What I usually post for this problem is time consuming, but detailed. I am an Electrical Engineer and found that whenever I try to piecemeal something, I always run into problems.

1. Turn off every component.
2. Unplug all power connections.
3. Unplug all interconnect connections.
4. Connect the speakers to the amp. Nothing else.
5. Turn on the amp only. Noise? No. continue. Yes, amp is the problem, or speaker cables. Turn off amp. Disconnect right speaker cable, turn on amp. Noise? no. continue. yes, interesting. Try different cables or raise them from the floor. If no change, amp is the problem.
6. Turn off the amp.
7. Connect pre-amp to amp, (speakers already connected).
8. Turn on pre-amp and amp. Noise? No. Continue. Yes, pre-amp or interconnect cable is the problem. Turn off components. Disconnect right interconnect cable. Turn on components. Noise? no. continue. Yes, change interconnect cables and try again. Noise? yes, try rerouting the cables away from noise making components. power cables, power supplies, etc.

The point here is to systematically connect one component at a time, until the hum begins to determine which component, cables, etc is causing the problem. Start with everything disconnected first and connect one thing at a time.

You will eventually find which component is causing the problem. Also, remember, that running interconnect cables anywhere near power sources or power cables is asking for hum trouble. If cables must cross, do so at ninety degree angles.

I run interconnect cables down one path, power cables down another and speaker cables down a different path and try hard to not have any close to the other or cross.
Also, I have run separate power feeds from my circuit breaker box for amps and for low level components. If you have a raised foundation, it is relatively easy to do this. But, a skilled electrician will not charge an arm and a leg for this. A few hundred dollars. Small change when you consider the cost of your equipment. So, my two amps have totally separate power outlets each independent to the power panel. My low level components (pre-amp, turn table, cd player, tuner, music server, crossover, DACs,) all feed into a power conditioner and that has its own power outlet that is independent to the panel as well. The benefits? Noise floors substantially dropped. No hum, no impact from dimmers or refrigerator, etc.) dead quiet.

But again, please, please, please do not use cheaters and lift the ground. you or your kids will become the ground and that is not good. Find and fix the problem.

enjoy.